Sport industry marketers have long understood the importance of nurturing customer relationships. The new challenge is how best to face the shifts in customer relationship marketing posed by sports organizations and proactive consumers, or “prosumers.” In this article, the elements of the relationship-building process are presented with a focus on communication, interaction, and value, concepts identified in Gronroos’s (2004) relationship-marketing process model. An expanded version of Gronroos’s model is developed to include prosumers and to describe the interactions that occur through social-media exchanges. The value of specific social-media tools and Web 2.0 technologies in helping sport marketers meet their relationship-marketing goals is also discussed. Finally, directions for future research employing the expanded model are suggested.